<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Responsive Layout Example</title>
    <style>
        .flex-container {
            display: flex;
            justify-content: space-between;
        }

        .flex-item {
            flex-grow: 1;
            text-align: start;
        }

        .flex-item input {
            height: 300px;
            text-align: start;
        }

        body {
            font-family: Arial, sans-serif;
            margin: 20px;
            padding: 20px;
            background-color: #f2f2f2;
        }

        h1 {
            color: #333;
        }

        p {
            line-height: 1.5;
        }

        /* 媒体查询 */
        @media screen and (max-width: 600px) {
            body {
                font-size: 14px;
            }

            h1 {
                font-size: 24px;
            }

            p {
                font-size: 16px;
            }
        }

        @media screen and (min-width: 601px) and (max-width: 900px) {
            body {
                font-size: 16px;
            }

            h1 {
                font-size: 32px;
            }

            p {
                font-size: 18px;
            }
        }

        @media screen and (min-width: 901px) {
            body {
                font-size: 18px;
            }

            h1 {
                font-size: 40px;
            }

            p {
                font-size: 20px;
            }
        }
    </style>
</head>

<body>
    <h1>Responsive Layout Example</h1>
    <p>This is a simple example of a responsive layout using media queries. The font size and heading size will change
        based on the screen width.</p>

    <div class="flex-container">
        <div class="flex-item">
            <input>
        </div>
        <div class="flex-item">
            <input>
        </div>
        <div class="flex-item">
            <input>
        </div>
    </div>
</body>

</html>